CVE-2021-43542

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CVSS 3.1

6.5 medium

EPSS

2%p76

Published

Dec 8, 2021 (Dec 8, 2021)

Modified

Jun 17, 2026

Description

Using XMLHttpRequest, an attacker could have identified installed applications by probing error messages for loading external protocols. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Vendors: mozilla debian
Products: firefox, firefox esr, thunderbird, debian linux
Weakness: CWE-209
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

NVD CVE.org GitHub PoCs EPSS (1.7%)

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